ITUB201558313U1 - DOSING SYSTEM - Google Patents

Description

"DOSING SYSTEM"

The invention relates to a dosing apparatus for dosing substances in powder, granules or flakes.

In particular, the invention relates to a dosing apparatus for dispensing, in a continuous or discontinuous manner, metered quantities of bulk products in a solid and dry state, that is, non-pasty or emulsified in any way.

The dosing apparatus for substances in powder, granules or flakes according to the invention is particularly suitable for use in the chemical, zootechnical, pharmaceutical or food industry. Other uses of the dosing apparatus according to the invention can however be envisaged.

The known metering apparatuses comprise a containment compartment for containing the substance in powder, granules or flakes. Inside the containment compartment there are two tools, namely a homogenizer tool and a dosing tool. The homogenizing tool prepares the substance making it uniform, while the dosing tool calibrates the amount of substance exiting the dosing apparatus, in accordance with a predetermined operating regime of this apparatus. The known metering apparatuses described above are defined as single screw, since they are equipped with a single metering tool or metering screw.

The homogenizing tool is placed near a feeding mouth from which the substance in powder, granules or flakes comes. It comprises a support stem which can rotate around its own longitudinal axis and is equipped with a plurality of vanes for mixing and / or aerating the substance in powder, granules or flakes. The dosing tool is instead arranged downstream of the homogenizing tool and is configured to dispense the substance in powder, granules or flakes in a dosed manner. The dosing tool, which can also rotate around its own longitudinal axis, may include a shaft on which a propeller is wound. During rotation, the dosing tool acts as a calibrated screw in which each turn of the shaft corresponds to a precise amount of substance delivered to the outlet of the dosing apparatus.

During operation, the known single-screw metering devices are positioned in such a way that a vertical plane, which contains the longitudinal axis of the homogenizing tool, also contains the longitudinal axis of the metering tool. In other words, the homogenizing tool and the dosing tool extend along their respective axes that lie on a common vertical plane.

A defect of known types of dosing equipment is that the substance in powder, granules or flakes tends to accumulate above the dosing tool, forming bridge structures that can extend along the entire length of the containment compartment. This affects the uniformity of homogenization, compromises the correct dosage of the output substance and could generate contamination or deterioration in those products, such as food products, which need to be dosed with precise timing.

In this context, the technical task of the present invention is to provide a dosing apparatus for substances in powder, granules or flakes that overcomes the aforementioned problem and all the limitations of use deriving from it.

It is the aim of the present invention to provide a dosing apparatus for substances in powder, granules or flakes that is effective and allows for homogenization and dosing of the substance in powder, granules or flakes in a repeatable and reliable manner.

These and other purposes are substantially achieved by a dosing apparatus for substances in powder, granules or flakes in accordance with what is described in one or more of the appended claims.

The dependent claims correspond to further embodiments of a metering device for substances in powder, granules or flakes according to the present invention.

Further characteristics and advantages will become clearer from the detailed description of a preferred and non-exclusive embodiment of a metering apparatus for substances in powder, granules or flakes.

This description is provided with reference to the accompanying figures, also having purely illustrative and therefore non-limiting purposes, in which: Figure 1 is a front perspective view showing a dosing apparatus for substances in powder, granules or flakes;

Figure 2 is a sectional view of the dosing apparatus of Figure 1, taken along a vertical plane perpendicular to a pair of axes of the respective tools of the dosing apparatus, and in which some parts have been removed for clarity of representation;

Figure 3 is a further sectional view of the dosing apparatus of Figure 1, taken along a vertical plane parallel to the axes of the dosing apparatus tools, from which some parts have been removed for clarity of representation.

With reference to Figures 1 to 3, reference 1 illustrates a metering apparatus for substances in powder, granules or flakes in accordance with the present invention. The dosing apparatus 1 allows to dose the substances in powder, granules or flakes with a relatively high precision and is therefore indicated by the experts also with the term "microdoser".

The dosing apparatus 1 comprises a dosing tool 10 and a homogenizing tool 20, as schematically illustrated for example in Figure 1.

The homogenizing tool 20 and the dosing tool 10 are operationally associated with each other in an operating configuration of the dosing apparatus 1. In particular, the homogenizing tool 20 is rotatable around a "Y" axis of rotation.

The dosing tool 10 is rotatable around a further rotation axis "X" and develops along this axis. The dosing tool 10 has a first end 11 and a second end 12.

Preferably, the "X" axis of rotation of the dosing tool 10 is parallel to the "Y" axis of rotation of the homogenizer tool 20.

The metering apparatus 1 comprises a containment chamber 30 delimited by a first end wall 31 and by a second end wall 32 facing each other and arranged transversely, in particular perpendicularly, with respect to the axis of rotation "Y" of the tool homogenizer 20. The second end wall 32 can be at least partially defined by a door 40, which can be removed for example by means of fastening means 41 visible in Figure 3. By acting on the fastening means 41, it is possible to disassemble the door 40 , so as to allow an operator to perform cleaning, maintenance and / or control operations on the dosing apparatus 1. The door 40 can comprise a transparent portion, so as to make the inside of the dosing apparatus 1 visible to the operator , even without the door 40 having to be removed.

The containment chamber 30 is also delimited by a lateral joining surface 33 which extends between the first end wall 31 and the second end wall 32 along a development direction "T" parallel to the axis of rotation "X".

The containment chamber 30 has rounded edges, so as to make the surface of this chamber as free as possible of sharp edges or corners of stagnation of the substance in powder, granules or flakes. This makes the emptying of the containment chamber 30 more efficient and improves the cleaning of the dosing apparatus 1, both because it is more difficult for the substance to be dosed to form stagnations outside the dosing apparatus 1, and because the dosing apparatus 1 it can be easily washed, in particular with water, without the washing water stagnating near sharp edges of the dosing apparatus 1.

Preferably, the containment chamber 30 has, in its own upper portion 30a, a feeding mouth 34 which can be connected, for example by means of a flanged portion, to a feeder or a hopper (not shown) for transporting the powder substances, granules or flakes inside the dosing apparatus 1.

The containment chamber 30 also has a lower portion 30b, in correspondence with which the substance in powder, granules or flakes is deposited in an operational configuration of the dosing apparatus 1.

Preferably, as shown in Figure 2, the lateral surface 33 of the containment chamber 30 includes two facing portions 33a, which in the example shown are substantially vertical, arranged on opposite sides of the "Y" rotation axis. Between the facing portions 33a a rounded portion 33b is interposed, which extends as a downward extension of one of the facing portions 33a. The rounded portion 33b extends at least partially around the rotation axis "Y" of the homogenizer tool 20, so as to at least partially delimit the lower portion 30b of the containment chamber 30. In the example shown, the rounded portion 33b is shaped around the axis of rotation "Y" and has a constant radius of curvature with respect to the aforementioned axis.

In a version not shown, the rounded section 33b may present, in a cross section taken along a plane perpendicular to the axis of rotation "Y", a non-constant radius of curvature. In the latter case, the rounded section 33b can be defined by a plurality of curvilinear sections shaped in such a way as to progressively approach the homogenizer tool 20, passing from the upper portion 30a to the lower portion 30b.

In other words, the rounded portion 33b can be shaped in such a way as to present a greater distance from the homogenizing tool 20 in the area in which this portion extends along a direction close to the vertical direction, and instead has a smaller distance from the tool. homogenizer 20 in the zone in which the rounded portion 33b extends along a substantially horizontal direction. In this way, it is possible to avoid stagnation of the processed substance.

The homogenizing tool 20 is installed on the dosing apparatus 1 in an intermediate area of the containment chamber 30, as better described below. In particular, the homogenizing tool 20 is arranged in such a way as to occupy a main portion 38 of the containment chamber 30.

The containment chamber 30 also has a housing 35 to house at least partially the dosing tool 10. The housing 35 extends from the first end wall 31 to the second end wall 32 along the development direction "T".

In the example shown, the housing 35 is formed inside a protuberance 39 which protrudes from the rounded portion 33b of the side surface 33. However, it is also possible to hypothesize a case in which the containment chamber 30 is delimited by walls having one thickness such that the housing 35 can be formed in the thickness of these walls. In this case, it is not possible to identify a protuberance 39 protruding outwards.

The housing 35 is configured to house the metering tool 10. A passage port 36, shown in Figures 2 and 3, communicates the main portion 38 of the containment chamber 30 with the housing 35, so that the powder material, granules or flakes, after interacting with the homogenizing tool 20, can pass into the housing 35 through the passage opening 36, to interact with the metering tool 10.

Preferably, the passage opening 36 extends along the direction of development "T" for a predetermined length.

In particular, the passage opening 36 extends along the development direction "T" for a length equal to the distance that exists between the first end wall 31 and the second end wall 32 of the containment chamber 30.

The housing 35 is arranged near the rounded section 33b of the side surface 33. More in detail, the housing 35 and the rounded section 33b are interposed between the facing sections 33a of the side surface 33.

Between the rounded portion 33b and the housing 35 there is a connection area 42 shaped in such a way as to facilitate the flow of the substance in powder, granules or flakes from the rounded portion 33b towards the housing 35. In particular, the connection area 42 has no edges. The first end 11 of the metering tool 10 is arranged in correspondence with the first wall 31 of the containment chamber 30. As shown in Figure 3, the metering tool 10 comprises an extraction section 13 defined starting from the first end 11 up to a portion of the metering tool 10 located in correspondence with the second end wall 32 of the containment chamber 30. The second end wall 32 is the wall arranged in proximity to an outlet 2 of the metering apparatus 1, or in any case it is the wall of the end closest to the outlet 2 of the dosing apparatus 1.

The outlet 2 is essentially an opening from which the substance in powder, granules or flakes comes out after interacting with the homogenizer tool 20 and with the dosing tool 10.

In the example shown, the extraction portion 13 of the metering tool 10 faces the passage opening 36 of the containment chamber 30. The passage opening 36 has, along a direction transverse to the development direction "T", a proportionate width to a measurement of an external diameter "D" of the dosing tool 10.

The metering apparatus 1 comprises positioning means 50, shown in Figures 1 and 2, for positioning the metering apparatus 1 with respect to a support structure, in an operative configuration, i.e. during operation, of the metering apparatus 1. The means positioning means 50 can comprise support means for resting the dosing apparatus 1 on the support structure, as happens in the example shown, in which the positioning means 50 are shaped like a base projecting from a rear portion of the dosing apparatus 1. However, the positioning means 50 can also be shaped differently from what is shown in the figures. For example, the positioning means 50 could comprise fixing means for fixing the dosing apparatus 1 to the support structure, in particular shaped like a fixing flange.

The housing 35 protrudes downwards from the lower portion 30b of the containment chamber 30.

The housing 35, and the metering tool 10 present inside it, is arranged in a lateral position with respect to the axis of rotation "Y" of the homogenizing tool 20. In other words, as shown in the attached Figure 2, in a operating configuration of the metering apparatus 1, the metering tool 10 is arranged laterally with respect to a vertical plane containing the axis of rotation "Y" of the homogenizing tool 20. In an operative configuration of the metering apparatus 1, a vertical plane P (the trace of which is shown in Figure 2) which contains the axis of rotation "Y" of the homogenizing tool 20, does not intersect the metering tool 10, that is, it passes outside the metering tool 10. The vertical plane P passes moreover outside the housing 35, as well as the protuberance 39. The vertical plane P intersects the rounded portion 33b of the containment chamber 30. The housing 35 projects from the rounded portion 33b of the containment chamber 30.

The housing 35 is delimited by an internal curved surface 35a, with respect to the containment chamber 30, suitable for mating at least partially with a respective portion of the dosing tool 10.

By internal curved surface 35a we mean an internal surface portion of the housing 35 which faces the containment chamber 30, i.e. it is in direct contact with the substance in powder / granules / flakes, in an operational configuration of the dosing apparatus 1.

Preferably, the curved surface 35a has a radius of curvature approximately equal to the external diameter "D" of the dosing tool 10.

The housing 35 is also delimited by a flat surface 35b which, in the operational configuration of the dosing apparatus 1, is arranged substantially vertically. The flat surface 35b extends tangentially from the curved surface 35a to a portion of the side surface 33 of the containment chamber 30, as schematically illustrated in Figure 2.

Preferably, the flat surface 35b is incident to a portion of the side surface 33 and acts as a connecting wall between the housing 35 and the side surface 33 of the containment chamber 30.

The homogenizing tool 20 is equipped with a plurality of mixing or aeration vanes 21 fixed on an attachment portion 22 of the homogenizing tool 20.

The plurality of vanes 21 can comprise two end vanes 21a, arranged in proximity to the first end wall 31 and respectively to the second end wall 32 of the containment chamber 30. The end vanes 21a have a relatively simple shape, and can be substantially flat and arranged obliquely with respect to the axis of rotation "Y". The end vanes 21a have the function of making the substance in powder, granules or flakes to be dosed flow towards a central area of the containment chamber 30.

The plurality of mixing blades 21 may also comprise a plurality of ploughshare-shaped blades 21b. Preferably, the ploughshare-shaped blades 21b are interposed between the end blades 21a.

The walls delimiting the containment chamber 30 can be made entirely of metal, or entirely of plastic, or else they can be provided with a coating of plastic material.

The walls of the containment chamber 30, if made of plastic material, can be associated with one or more facilitating devices for the descent of the product, for example vibrators or oscillators of the electric, pneumatic or mechanical vane type, to make the walls of the containment chamber vibrate. 30 and help the processed substance to flow towards the outlet, or more precisely towards the dosing tool 10. The devices facilitating the descent of the product can be applied outside the walls of the containment chamber 30 or integrated, at least partially, into the thickness of such walls.

The dosing apparatus 1 allows to substantially reduce the accumulations of substance to be dosed above the dosing tool 10, compared to known dosing apparatuses. In fact, by moving the dosing tool 10 laterally with respect to the homogenizing tool 20, the substance in powder, granules or flakes can more easily be brought to the outlet 2 during the rotation of the dosing tool 10.

This effect is amplified by the flat surface 35b of the housing 35. In fact, the substance in powder, granules or flakes which is transported upwards during the rotation of the metering tool 10 is unable to adhere to the flat surface 35b, which is arranged substantially vertically, but tends to slide downwards, detaching itself from the flat surface 35b. In this way, the substance in powder, granules or flakes then returns to interact with the dosing tool 10, which transports it to the outlet 2.

In the example described with reference to Figures 1 to 3, reference has always been made to a dosing apparatus 1 which can be defined as "single screw", as it is equipped with a single dosing tool 10, or a single dosing screw. However, the metering apparatus according to the invention can also be of the type defined as "twin screw", ie provided with two metering tools 10 arranged to dose the substance in powder, granules or flakes which has been previously processed by a single homogenizing tool 20. In this case, a housing 35 is preferably provided, configured to house the two corresponding metering tools. The dosing tools are counter-rotating with respect to each other. In an operational configuration of this dosing apparatus, a vertical plane passing through the "Y" axis of rotation of the homogenizing tool 20 lies outside the housing 35. This plane does not intersect the dosing tools.

The two dosing tools of the twin screw dosing device interpenetrate and self-clean. They can be separated by a small insert, with a substantially triangular section, aimed at filling an empty space present between the dosing tools, below the latter.

The present invention has achieved the intended aim and objects by making available a more efficient metering apparatus, which is capable of carrying out a homogenization and metering of the bulk substance in a precise manner, repeatable at each operating regime of the same. Furthermore, the present invention provides a dosing apparatus capable of homogenizing the bulk substance contained within it without accumulation, preventing aggregations and residues of the processed substance, ensuring high dosing accuracy and ease of cleaning.

Claims (16)

CLAIMS 1. Dosing apparatus (1) for dosing a substance in powder, granules or flakes, comprising: - a containment chamber (30) for receiving said substance; - a homogenizing tool (20) arranged inside the containment chamber (30) and rotating around an axis (Y) to homogenize said substance; - a metering tool (10) rotatable around a further axis (X) to convey metered quantities of said substance out of the containment chamber (30); - positioning means (50) to position the dosing apparatus (1) with respect to a support structure in an operational configuration; characterized in that said further axis (X) is offset with respect to said axis (Y), so that, in said operating configuration, a vertical plane (P) containing said axis (Y) passes outside the metering tool (10) . 2. Metering apparatus (1) according to claim 1, wherein the metering tool (10) is arranged inside a housing (35) communicating with a main portion (38) of the containment chamber (30) in which it is arranged the homogenizing tool (20), said vertical plane (P) passing outside the housing (35), in the operative configuration. Metering apparatus (1) according to claim 2, wherein said housing (35) is internally delimited by a curved surface (35a) partially surrounding the metering tool (10) and by a flat surface (35b) which connects said surface curved (35a) with the main portion (38) of the containment chamber (30), said flat surface (35b) being arranged substantially vertically in the operative configuration. 4. Dosing apparatus (1) according to claim 2 or 3, in which the housing (35) is obtained inside a protuberance (39) that protrudes from a lower region (30b) of the containment chamber (30). Metering apparatus according to one of claims 2 to 4, wherein the housing (35) communicates with the main portion (38) of the containment chamber (30) by means of a passage opening (36) through which it can flow said substance. 6. Metering apparatus (1) according to one of the preceding claims, in which the containment chamber (30) is defined by a first end wall (31) and a second end wall (32), facing each other and arranged transversely with respect to said axis (Y), the containment chamber (30) being further defined by a lateral surface (33) which joins said first end wall (31) and said second end wall (32). Metering apparatus (1) according to claim 6, when dependent on claim 5, wherein the passage opening (36) extends from the first end wall (31) to the second end wall (32). 8. Metering apparatus (1) according to claim 6 or 7, wherein the lateral surface (33) of the containment chamber (30) comprises a rounded portion (33b) extending at least partially around said axis (Y) and having a profile curvilinear. Dosage apparatus (1) according to claim 8, wherein, in the operative configuration, said vertical plane (P) intersects the rounded portion (33b). Metering apparatus (1) according to claim 8 or 9, when claim 8 depends on claim 2, wherein said housing (35) protrudes from the rounded portion (33b) of the containment chamber (30). 11. Dosing apparatus (1) according to one of the preceding claims, wherein said homogenizing tool (20) is provided with two end regions in each of which an end blade (21a) is arranged, the end blades (21a) being shaped to convey said substance in a central area of the containment chamber (30). Metering apparatus (1) according to one of the preceding claims, in which a single metering tool (10) is provided. 13. Metering apparatus (1) according to one of claims 1 to 11, and further comprising a further metering tool cooperating with said metering tool (10) to convey metered quantities of said substance out of the containment chamber (30). Metering apparatus (1) according to claim 13, wherein said further metering tool is rotatable around a corresponding axis offset with respect to said axis (Y) so that, in the operating configuration, said vertical plane (P) passes outside of said metering tool (10) and said further metering tool. Dosing apparatus (1) according to one of the preceding claims, having a body at least partially made of plastic material. 16. Dosing apparatus (1) according to one of the preceding claims, and further comprising at least one descent facilitator device for facilitating the descent of said substance into the containment chamber (30).